Variable expansion

Any string value in the config file supports two substitutions.

${workspaceFolder}

The directory containing the config file. See relative paths.

${env:VAR_NAME}

The value of that environment variable.

Together they keep machine-specific paths and secrets out of the file itself, which means the config can be committed.

mcp-config.json

{
  "mcpServers": {
    "filesystem": {
      "command": "npx",
      "args": [
        "-y",
        "@modelcontextprotocol/server-filesystem",
        "${workspaceFolder}/data"
      ]
    },
    "remote_with_headers": {
      "url": "https://example.com/mcp",
      "headers": {
        "X-Client-Name": "ollama-mcp-bridge",
        "X-Request-Tag": "${env:MCP_REQUEST_TAG}"
      }
    }
  }
}

Tip

${env:...} is the right place for API keys on remote MCP servers. For credentials aimed at whatever sits between the bridge and Ollama, use upstream headers instead — those are a different hop.